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Diffstat (limited to 'src/wc.c')
| -rw-r--r-- | src/wc.c | 895 |
1 files changed, 895 insertions, 0 deletions
diff --git a/src/wc.c b/src/wc.c new file mode 100644 index 0000000..d18eaee --- /dev/null +++ b/src/wc.c @@ -0,0 +1,895 @@ +/* wc - print the number of lines, words, and bytes in files + Copyright (C) 1985-2020 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by Paul Rubin, phr@ocf.berkeley.edu + and David MacKenzie, djm@gnu.ai.mit.edu. */ + +#include <config.h> + +#include <stdio.h> +#include <assert.h> +#include <getopt.h> +#include <sys/types.h> +#include <wchar.h> +#include <wctype.h> + +#include "system.h" +#include "argv-iter.h" +#include "die.h" +#include "error.h" +#include "fadvise.h" +#include "mbchar.h" +#include "physmem.h" +#include "readtokens0.h" +#include "safe-read.h" +#include "stat-size.h" +#include "xbinary-io.h" + +#if !defined iswspace && !HAVE_ISWSPACE +# define iswspace(wc) \ + ((wc) == to_uchar (wc) && isspace (to_uchar (wc))) +#endif + +/* The official name of this program (e.g., no 'g' prefix). */ +#define PROGRAM_NAME "wc" + +#define AUTHORS \ + proper_name ("Paul Rubin"), \ + proper_name ("David MacKenzie") + +/* Size of atomic reads. */ +#define BUFFER_SIZE (16 * 1024) + +/* Cumulative number of lines, words, chars and bytes in all files so far. + max_line_length is the maximum over all files processed so far. */ +static uintmax_t total_lines; +static uintmax_t total_words; +static uintmax_t total_chars; +static uintmax_t total_bytes; +static uintmax_t max_line_length; + +/* Which counts to print. */ +static bool print_lines, print_words, print_chars, print_bytes; +static bool print_linelength; + +/* The print width of each count. */ +static int number_width; + +/* True if we have ever read the standard input. */ +static bool have_read_stdin; + +/* Used to determine if file size can be determined without reading. */ +static size_t page_size; + +/* Enable to _not_ treat non breaking space as a word separator. */ +static bool posixly_correct; + +/* The result of calling fstat or stat on a file descriptor or file. */ +struct fstatus +{ + /* If positive, fstat or stat has not been called yet. Otherwise, + this is the value returned from fstat or stat. */ + int failed; + + /* If FAILED is zero, this is the file's status. */ + struct stat st; +}; + +/* For long options that have no equivalent short option, use a + non-character as a pseudo short option, starting with CHAR_MAX + 1. */ +enum +{ + FILES0_FROM_OPTION = CHAR_MAX + 1 +}; + +static struct option const longopts[] = +{ + {"bytes", no_argument, NULL, 'c'}, + {"chars", no_argument, NULL, 'm'}, + {"lines", no_argument, NULL, 'l'}, + {"words", no_argument, NULL, 'w'}, + {"files0-from", required_argument, NULL, FILES0_FROM_OPTION}, + {"max-line-length", no_argument, NULL, 'L'}, + {GETOPT_HELP_OPTION_DECL}, + {GETOPT_VERSION_OPTION_DECL}, + {NULL, 0, NULL, 0} +}; + +void +usage (int status) +{ + if (status != EXIT_SUCCESS) + emit_try_help (); + else + { + printf (_("\ +Usage: %s [OPTION]... [FILE]...\n\ + or: %s [OPTION]... --files0-from=F\n\ +"), + program_name, program_name); + fputs (_("\ +Print newline, word, and byte counts for each FILE, and a total line if\n\ +more than one FILE is specified. A word is a non-zero-length sequence of\n\ +characters delimited by white space.\n\ +"), stdout); + + emit_stdin_note (); + + fputs (_("\ +\n\ +The options below may be used to select which counts are printed, always in\n\ +the following order: newline, word, character, byte, maximum line length.\n\ + -c, --bytes print the byte counts\n\ + -m, --chars print the character counts\n\ + -l, --lines print the newline counts\n\ +"), stdout); + fputs (_("\ + --files0-from=F read input from the files specified by\n\ + NUL-terminated names in file F;\n\ + If F is - then read names from standard input\n\ + -L, --max-line-length print the maximum display width\n\ + -w, --words print the word counts\n\ +"), stdout); + fputs (HELP_OPTION_DESCRIPTION, stdout); + fputs (VERSION_OPTION_DESCRIPTION, stdout); + emit_ancillary_info (PROGRAM_NAME); + } + exit (status); +} + +/* Return non zero if a non breaking space. */ +static int _GL_ATTRIBUTE_PURE +iswnbspace (wint_t wc) +{ + return ! posixly_correct + && (wc == 0x00A0 || wc == 0x2007 + || wc == 0x202F || wc == 0x2060); +} + +static int +isnbspace (int c) +{ + return iswnbspace (btowc (c)); +} + +/* FILE is the name of the file (or NULL for standard input) + associated with the specified counters. */ +static void +write_counts (uintmax_t lines, + uintmax_t words, + uintmax_t chars, + uintmax_t bytes, + uintmax_t linelength, + const char *file) +{ + static char const format_sp_int[] = " %*s"; + char const *format_int = format_sp_int + 1; + char buf[INT_BUFSIZE_BOUND (uintmax_t)]; + + if (print_lines) + { + printf (format_int, number_width, umaxtostr (lines, buf)); + format_int = format_sp_int; + } + if (print_words) + { + printf (format_int, number_width, umaxtostr (words, buf)); + format_int = format_sp_int; + } + if (print_chars) + { + printf (format_int, number_width, umaxtostr (chars, buf)); + format_int = format_sp_int; + } + if (print_bytes) + { + printf (format_int, number_width, umaxtostr (bytes, buf)); + format_int = format_sp_int; + } + if (print_linelength) + { + printf (format_int, number_width, umaxtostr (linelength, buf)); + } + if (file) + printf (" %s", strchr (file, '\n') ? quotef (file) : file); + putchar ('\n'); +} + +/* Count words. FILE_X is the name of the file (or NULL for standard + input) that is open on descriptor FD. *FSTATUS is its status. + CURRENT_POS is the current file offset if known, negative if unknown. + Return true if successful. */ +static bool +wc (int fd, char const *file_x, struct fstatus *fstatus, off_t current_pos) +{ + bool ok = true; + char buf[BUFFER_SIZE + 1]; + size_t bytes_read; + uintmax_t lines, words, chars, bytes, linelength; + bool count_bytes, count_chars, count_complicated; + char const *file = file_x ? file_x : _("standard input"); + + lines = words = chars = bytes = linelength = 0; + + /* If in the current locale, chars are equivalent to bytes, we prefer + counting bytes, because that's easier. */ +#if MB_LEN_MAX > 1 + if (MB_CUR_MAX > 1) + { + count_bytes = print_bytes; + count_chars = print_chars; + } + else +#endif + { + count_bytes = print_bytes || print_chars; + count_chars = false; + } + count_complicated = print_words || print_linelength; + + /* Advise the kernel of our access pattern only if we will read(). */ + if (!count_bytes || count_chars || print_lines || count_complicated) + fdadvise (fd, 0, 0, FADVISE_SEQUENTIAL); + + /* When counting only bytes, save some line- and word-counting + overhead. If FD is a 'regular' Unix file, using lseek is enough + to get its 'size' in bytes. Otherwise, read blocks of BUFFER_SIZE + bytes at a time until EOF. Note that the 'size' (number of bytes) + that wc reports is smaller than stats.st_size when the file is not + positioned at its beginning. That's why the lseek calls below are + necessary. For example the command + '(dd ibs=99k skip=1 count=0; ./wc -c) < /etc/group' + should make wc report '0' bytes. */ + + if (count_bytes && !count_chars && !print_lines && !count_complicated) + { + bool skip_read = false; + + if (0 < fstatus->failed) + fstatus->failed = fstat (fd, &fstatus->st); + + /* For sized files, seek to one st_blksize before EOF rather than to EOF. + This works better for files in proc-like file systems where + the size is only approximate. */ + if (! fstatus->failed && usable_st_size (&fstatus->st) + && 0 <= fstatus->st.st_size) + { + size_t end_pos = fstatus->st.st_size; + if (current_pos < 0) + current_pos = lseek (fd, 0, SEEK_CUR); + + if (end_pos % page_size) + { + /* We only need special handling of /proc and /sys files etc. + when they're a multiple of PAGE_SIZE. In the common case + for files with st_size not a multiple of PAGE_SIZE, + it's more efficient and accurate to use st_size. + + Be careful here. The current position may actually be + beyond the end of the file. As in the example above. */ + + bytes = end_pos < current_pos ? 0 : end_pos - current_pos; + skip_read = true; + } + else + { + off_t hi_pos = end_pos - end_pos % (ST_BLKSIZE (fstatus->st) + 1); + if (0 <= current_pos && current_pos < hi_pos + && 0 <= lseek (fd, hi_pos, SEEK_CUR)) + bytes = hi_pos - current_pos; + } + } + + if (! skip_read) + { + fdadvise (fd, 0, 0, FADVISE_SEQUENTIAL); + while ((bytes_read = safe_read (fd, buf, BUFFER_SIZE)) > 0) + { + if (bytes_read == SAFE_READ_ERROR) + { + error (0, errno, "%s", quotef (file)); + ok = false; + break; + } + bytes += bytes_read; + } + } + } + else if (!count_chars && !count_complicated) + { + /* Use a separate loop when counting only lines or lines and bytes -- + but not chars or words. */ + bool long_lines = false; + while ((bytes_read = safe_read (fd, buf, BUFFER_SIZE)) > 0) + { + if (bytes_read == SAFE_READ_ERROR) + { + error (0, errno, "%s", quotef (file)); + ok = false; + break; + } + + bytes += bytes_read; + + char *p = buf; + char *end = p + bytes_read; + uintmax_t plines = lines; + + if (! long_lines) + { + /* Avoid function call overhead for shorter lines. */ + while (p != end) + lines += *p++ == '\n'; + } + else + { + /* memchr is more efficient with longer lines. */ + while ((p = memchr (p, '\n', end - p))) + { + ++p; + ++lines; + } + } + + /* If the average line length in the block is >= 15, then use + memchr for the next block, where system specific optimizations + may outweigh function call overhead. + FIXME: This line length was determined in 2015, on both + x86_64 and ppc64, but it's worth re-evaluating in future with + newer compilers, CPUs, or memchr() implementations etc. */ + if (lines - plines <= bytes_read / 15) + long_lines = true; + else + long_lines = false; + } + } +#if MB_LEN_MAX > 1 +# define SUPPORT_OLD_MBRTOWC 1 + else if (MB_CUR_MAX > 1) + { + bool in_word = false; + uintmax_t linepos = 0; + mbstate_t state = { 0, }; + bool in_shift = false; +# if SUPPORT_OLD_MBRTOWC + /* Back-up the state before each multibyte character conversion and + move the last incomplete character of the buffer to the front + of the buffer. This is needed because we don't know whether + the 'mbrtowc' function updates the state when it returns -2, -- + this is the ISO C 99 and glibc-2.2 behaviour - or not - amended + ANSI C, glibc-2.1 and Solaris 5.7 behaviour. We don't have an + autoconf test for this, yet. */ + size_t prev = 0; /* number of bytes carried over from previous round */ +# else + const size_t prev = 0; +# endif + + while ((bytes_read = safe_read (fd, buf + prev, BUFFER_SIZE - prev)) > 0) + { + const char *p; +# if SUPPORT_OLD_MBRTOWC + mbstate_t backup_state; +# endif + if (bytes_read == SAFE_READ_ERROR) + { + error (0, errno, "%s", quotef (file)); + ok = false; + break; + } + + bytes += bytes_read; + p = buf; + bytes_read += prev; + do + { + wchar_t wide_char; + size_t n; + bool wide = true; + + if (!in_shift && is_basic (*p)) + { + /* Handle most ASCII characters quickly, without calling + mbrtowc(). */ + n = 1; + wide_char = *p; + wide = false; + } + else + { + in_shift = true; +# if SUPPORT_OLD_MBRTOWC + backup_state = state; +# endif + n = mbrtowc (&wide_char, p, bytes_read, &state); + if (n == (size_t) -2) + { +# if SUPPORT_OLD_MBRTOWC + state = backup_state; +# endif + break; + } + if (n == (size_t) -1) + { + /* Remember that we read a byte, but don't complain + about the error. Because of the decoding error, + this is a considered to be byte but not a + character (that is, chars is not incremented). */ + p++; + bytes_read--; + continue; + } + if (mbsinit (&state)) + in_shift = false; + if (n == 0) + { + wide_char = 0; + n = 1; + } + } + + switch (wide_char) + { + case '\n': + lines++; + FALLTHROUGH; + case '\r': + case '\f': + if (linepos > linelength) + linelength = linepos; + linepos = 0; + goto mb_word_separator; + case '\t': + linepos += 8 - (linepos % 8); + goto mb_word_separator; + case ' ': + linepos++; + FALLTHROUGH; + case '\v': + mb_word_separator: + words += in_word; + in_word = false; + break; + default: + if (wide && iswprint (wide_char)) + { + /* wcwidth can be expensive on OSX for example, + so avoid if uneeded. */ + if (print_linelength) + { + int width = wcwidth (wide_char); + if (width > 0) + linepos += width; + } + if (iswspace (wide_char) || iswnbspace (wide_char)) + goto mb_word_separator; + in_word = true; + } + else if (!wide && isprint (to_uchar (*p))) + { + linepos++; + if (isspace (to_uchar (*p))) + goto mb_word_separator; + in_word = true; + } + break; + } + + p += n; + bytes_read -= n; + chars++; + } + while (bytes_read > 0); + +# if SUPPORT_OLD_MBRTOWC + if (bytes_read > 0) + { + if (bytes_read == BUFFER_SIZE) + { + /* Encountered a very long redundant shift sequence. */ + p++; + bytes_read--; + } + memmove (buf, p, bytes_read); + } + prev = bytes_read; +# endif + } + if (linepos > linelength) + linelength = linepos; + words += in_word; + } +#endif + else + { + bool in_word = false; + uintmax_t linepos = 0; + + while ((bytes_read = safe_read (fd, buf, BUFFER_SIZE)) > 0) + { + const char *p = buf; + if (bytes_read == SAFE_READ_ERROR) + { + error (0, errno, "%s", quotef (file)); + ok = false; + break; + } + + bytes += bytes_read; + do + { + switch (*p++) + { + case '\n': + lines++; + FALLTHROUGH; + case '\r': + case '\f': + if (linepos > linelength) + linelength = linepos; + linepos = 0; + goto word_separator; + case '\t': + linepos += 8 - (linepos % 8); + goto word_separator; + case ' ': + linepos++; + FALLTHROUGH; + case '\v': + word_separator: + words += in_word; + in_word = false; + break; + default: + if (isprint (to_uchar (p[-1]))) + { + linepos++; + if (isspace (to_uchar (p[-1])) + || isnbspace (to_uchar (p[-1]))) + goto word_separator; + in_word = true; + } + break; + } + } + while (--bytes_read); + } + if (linepos > linelength) + linelength = linepos; + words += in_word; + } + + if (count_chars < print_chars) + chars = bytes; + + write_counts (lines, words, chars, bytes, linelength, file_x); + total_lines += lines; + total_words += words; + total_chars += chars; + total_bytes += bytes; + if (linelength > max_line_length) + max_line_length = linelength; + + return ok; +} + +static bool +wc_file (char const *file, struct fstatus *fstatus) +{ + if (! file || STREQ (file, "-")) + { + have_read_stdin = true; + xset_binary_mode (STDIN_FILENO, O_BINARY); + return wc (STDIN_FILENO, file, fstatus, -1); + } + else + { + int fd = open (file, O_RDONLY | O_BINARY); + if (fd == -1) + { + error (0, errno, "%s", quotef (file)); + return false; + } + else + { + bool ok = wc (fd, file, fstatus, 0); + if (close (fd) != 0) + { + error (0, errno, "%s", quotef (file)); + return false; + } + return ok; + } + } +} + +/* Return the file status for the NFILES files addressed by FILE. + Optimize the case where only one number is printed, for just one + file; in that case we can use a print width of 1, so we don't need + to stat the file. Handle the case of (nfiles == 0) in the same way; + that happens when we don't know how long the list of file names will be. */ + +static struct fstatus * +get_input_fstatus (size_t nfiles, char *const *file) +{ + struct fstatus *fstatus = xnmalloc (nfiles ? nfiles : 1, sizeof *fstatus); + + if (nfiles == 0 + || (nfiles == 1 + && ((print_lines + print_words + print_chars + + print_bytes + print_linelength) + == 1))) + fstatus[0].failed = 1; + else + { + for (size_t i = 0; i < nfiles; i++) + fstatus[i].failed = (! file[i] || STREQ (file[i], "-") + ? fstat (STDIN_FILENO, &fstatus[i].st) + : stat (file[i], &fstatus[i].st)); + } + + return fstatus; +} + +/* Return a print width suitable for the NFILES files whose status is + recorded in FSTATUS. Optimize the same special case that + get_input_fstatus optimizes. */ + +static int _GL_ATTRIBUTE_PURE +compute_number_width (size_t nfiles, struct fstatus const *fstatus) +{ + int width = 1; + + if (0 < nfiles && fstatus[0].failed <= 0) + { + int minimum_width = 1; + uintmax_t regular_total = 0; + + for (size_t i = 0; i < nfiles; i++) + if (! fstatus[i].failed) + { + if (S_ISREG (fstatus[i].st.st_mode)) + regular_total += fstatus[i].st.st_size; + else + minimum_width = 7; + } + + for (; 10 <= regular_total; regular_total /= 10) + width++; + if (width < minimum_width) + width = minimum_width; + } + + return width; +} + + +int +main (int argc, char **argv) +{ + bool ok; + int optc; + size_t nfiles; + char **files; + char *files_from = NULL; + struct fstatus *fstatus; + struct Tokens tok; + + initialize_main (&argc, &argv); + set_program_name (argv[0]); + setlocale (LC_ALL, ""); + bindtextdomain (PACKAGE, LOCALEDIR); + textdomain (PACKAGE); + + atexit (close_stdout); + + page_size = getpagesize (); + /* Line buffer stdout to ensure lines are written atomically and immediately + so that processes running in parallel do not intersperse their output. */ + setvbuf (stdout, NULL, _IOLBF, 0); + + posixly_correct = (getenv ("POSIXLY_CORRECT") != NULL); + + print_lines = print_words = print_chars = print_bytes = false; + print_linelength = false; + total_lines = total_words = total_chars = total_bytes = max_line_length = 0; + + while ((optc = getopt_long (argc, argv, "clLmw", longopts, NULL)) != -1) + switch (optc) + { + case 'c': + print_bytes = true; + break; + + case 'm': + print_chars = true; + break; + + case 'l': + print_lines = true; + break; + + case 'w': + print_words = true; + break; + + case 'L': + print_linelength = true; + break; + + case FILES0_FROM_OPTION: + files_from = optarg; + break; + + case_GETOPT_HELP_CHAR; + + case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS); + + default: + usage (EXIT_FAILURE); + } + + if (! (print_lines || print_words || print_chars || print_bytes + || print_linelength)) + print_lines = print_words = print_bytes = true; + + bool read_tokens = false; + struct argv_iterator *ai; + if (files_from) + { + FILE *stream; + + /* When using --files0-from=F, you may not specify any files + on the command-line. */ + if (optind < argc) + { + error (0, 0, _("extra operand %s"), quoteaf (argv[optind])); + fprintf (stderr, "%s\n", + _("file operands cannot be combined with --files0-from")); + usage (EXIT_FAILURE); + } + + if (STREQ (files_from, "-")) + stream = stdin; + else + { + stream = fopen (files_from, "r"); + if (stream == NULL) + die (EXIT_FAILURE, errno, _("cannot open %s for reading"), + quoteaf (files_from)); + } + + /* Read the file list into RAM if we can detect its size and that + size is reasonable. Otherwise, we'll read a name at a time. */ + struct stat st; + if (fstat (fileno (stream), &st) == 0 + && S_ISREG (st.st_mode) + && st.st_size <= MIN (10 * 1024 * 1024, physmem_available () / 2)) + { + read_tokens = true; + readtokens0_init (&tok); + if (! readtokens0 (stream, &tok) || fclose (stream) != 0) + die (EXIT_FAILURE, 0, _("cannot read file names from %s"), + quoteaf (files_from)); + files = tok.tok; + nfiles = tok.n_tok; + ai = argv_iter_init_argv (files); + } + else + { + files = NULL; + nfiles = 0; + ai = argv_iter_init_stream (stream); + } + } + else + { + static char *stdin_only[] = { NULL }; + files = (optind < argc ? argv + optind : stdin_only); + nfiles = (optind < argc ? argc - optind : 1); + ai = argv_iter_init_argv (files); + } + + if (!ai) + xalloc_die (); + + fstatus = get_input_fstatus (nfiles, files); + number_width = compute_number_width (nfiles, fstatus); + + ok = true; + for (int i = 0; /* */; i++) + { + bool skip_file = false; + enum argv_iter_err ai_err; + char *file_name = argv_iter (ai, &ai_err); + if (!file_name) + { + switch (ai_err) + { + case AI_ERR_EOF: + goto argv_iter_done; + case AI_ERR_READ: + error (0, errno, _("%s: read error"), + quotef (files_from)); + ok = false; + goto argv_iter_done; + case AI_ERR_MEM: + xalloc_die (); + default: + assert (!"unexpected error code from argv_iter"); + } + } + if (files_from && STREQ (files_from, "-") && STREQ (file_name, "-")) + { + /* Give a better diagnostic in an unusual case: + printf - | wc --files0-from=- */ + error (0, 0, _("when reading file names from stdin, " + "no file name of %s allowed"), + quoteaf (file_name)); + skip_file = true; + } + + if (!file_name[0]) + { + /* Diagnose a zero-length file name. When it's one + among many, knowing the record number may help. + FIXME: currently print the record number only with + --files0-from=FILE. Maybe do it for argv, too? */ + if (files_from == NULL) + error (0, 0, "%s", _("invalid zero-length file name")); + else + { + /* Using the standard 'filename:line-number:' prefix here is + not totally appropriate, since NUL is the separator, not NL, + but it might be better than nothing. */ + unsigned long int file_number = argv_iter_n_args (ai); + error (0, 0, "%s:%lu: %s", quotef (files_from), + file_number, _("invalid zero-length file name")); + } + skip_file = true; + } + + if (skip_file) + ok = false; + else + ok &= wc_file (file_name, &fstatus[nfiles ? i : 0]); + + if (! nfiles) + fstatus[0].failed = 1; + } + argv_iter_done: + + /* No arguments on the command line is fine. That means read from stdin. + However, no arguments on the --files0-from input stream is an error + means don't read anything. */ + if (ok && !files_from && argv_iter_n_args (ai) == 0) + ok &= wc_file (NULL, &fstatus[0]); + + if (read_tokens) + readtokens0_free (&tok); + + if (1 < argv_iter_n_args (ai)) + write_counts (total_lines, total_words, total_chars, total_bytes, + max_line_length, _("total")); + + argv_iter_free (ai); + + free (fstatus); + + if (have_read_stdin && close (STDIN_FILENO) != 0) + die (EXIT_FAILURE, errno, "-"); + + return ok ? EXIT_SUCCESS : EXIT_FAILURE; +} |